主序前星作为恒星演化的起点，这一阶段的演化将决定恒星的质量、金属丰度等伴随和影响恒星一生的参数。主序前星是恒星演化中的一个重要阶段，在研究恒星形成和演化的研究中具有极其重要的作用，因此，一个完备的覆盖太阳近邻主序前星的样本对恒星演化的研究是非常必要的。星协是同时形成于同一星云的成协恒星，相比于引力束缚的星团来说，星协成员星较少且相对松散。年轻星协中包含大量的主序前星，所占比例随星协年龄的大小（形成时间的早晚）而或多或少。由于成员星年轻且同源，年轻星协在多维相空间中具有明显的成团性，可以利用这一特点从周围场星中将年轻星协搜寻出来。同时，因为其成员星仍然保留着其诞生星云的运动学信息，年轻星协也可以用来示踪其宿主恒星形成区的运动趋势和物质演化。本项目将基于LAMOST逾千万条光谱和GAIA的天测、测光数据，搜寻近邻恒星形成区中的主序前星和年轻星协，并示踪恒星形成区的运动和物质演化。

Pre-main sequence stars (PMS stars) are the initial stage of stellar evolution, on this stage the mass, metallicity of a star are decided, thus the PMS stars are very important in study the formation and evolution of stars. Nearby PMS stars are particularly important, since stars in the PMS stage are brighter and easy detected than their counterpart of main sequence stage, and can be used as perfect probe of initial mass function (IMF) and early stage evolution of stars. In light of this, searching for a more completer sample space of nearby PMS stars are indispensably necessary. Associations are stars coevally formed from same molecular cloud. Compared with stars of clusters which are tightly bounded by gravity, members of the associations are loosely connected and largely extended in the space. Young stellar associations are consisted by tens to several hundreds stars of young, including a considerable extent of PMS stars. The proportion of PMS stars of a young stellar association are ascribed to the age of it, the younger the higher. Due to homology of its members, young stellar associations can be located from its surrounding field stars by the clustering of its members in the multi-dimensional astrometric space. Meanwhile, based on kinematics of young association stars, the movement tendency and interstellar medium (ISM) evolution of its host star formation region can also be deduced. In considering of this, based on the data set of LAMOST and GAIA, in this project we will search for a much more complete catalogue of PMS stars and young stellar associations as well as the kinematics and ISM evolution of nearby star formation region.